CHARA'CE4E, Charas, the Chasm Tribe, a curious group of plants inhabiting pools and slow streams, to which they communicate a nauseous offensive odour, which is said to become a pestilential miasma, when, as in the Campagna of Rome, the plants are in great numbers. They are jointed leafless plants, with verticillate branches, composed either of one or of several tubes adhering in bundles, and either encrusted with calcareous matter (Ohara), or transparent (Nitella). The reproductive organs are of two kinds. One named a nucule, is an oval sessile .spirally striated body, with a five-cleft apex, and a number of grains in its interior; this has been looked upon as the pistil, and has been seen to grow into a young plant. The other, called the globule, is a reddish body consisting of triangular scales, indorsing a mass of elastic wavy threads, and has been named au anther.
C. Senegalensis, the Senegal Chameleon. It is the Lacerta Chameleon of Lintimus ; C. Bonen; Spei of Laurent ; L. pumila of Gmelin. It is a native of the West of Africa.
C. dilegis, the Flap-Necked Chameleon. Found in Africa. Speci mens iu the British Museum have come from Fantee, Ashantee, Gambroon, and Senegal.
tt Scales unequal, larger tubercles. Muzzle simple.
C. Pardalis, the Bourbon Chameleon. A native of Bourbon. a verrucosus, the Warty Chameleon. It inhabits Madagascar. ttt Scales unequaL Muzzle (of male) with a central prominence. C. Rhinoceratus, the Rhinoceros-Chameleon. A native of Madagascar.
Specimens of this and the last species were presented to the British Museum by Sir Edward Belcher.
••'• Back with a toothed crest. Belly and sides simple.
t Chin and muzzle simple.
C. tuberculifcrus, the Tuberculated Chameleon. A native of South Africa.
C. cucullatus, the Hooded Chameleon. An inhabitant of Mada gascar.
-Ft Chin simple ; muzzle compressed, produced.
C. nasutus, the Sharp-Nosed Chameleon. A native of Madagascar. Chin simple; muzzle of male forked.
C. Warms, the Large-Napod Chameleon. A native of Madagascar. Chin bearded ; muzzle simple.
C. Tigris, the Fringed Chameleon. Found in the Seychelle Islands. C. rentralis, the Belly-Shaped Chameleon. Found in South Africa. C. pumilus, the Pearled Chameleon. A native of the Cape of Good Hope.
The following is Schleiden's description of these organs :—" On the lateral branches, generally in the axis of the above.mentioned pair of cells, five cells may be seen spirally wound round a thick mass, and having their parallel extremities surrounded by a kind of pentagonal crown. From this thick granular mass a large cell (spore) is formed, filled with large granules of starch, mucus, and oil-globules, and with a substance that closely invests the spore-cells ; and from being.at first transparent subsequently becomes green or red, and finally black. The five investing cells then either become cartilaginous, and remain until the whole decays after germination, or they are converted into a felatinous state, and then speedily dissolved after the sporocarp has fallen. Close below this aporocarp there may generally be seen, nt the same time, seated upou a short cylindrical cell, another cell, which is at first simple and spherical, but from which eight [query always eight I] cells are gradually developed, which become flattened, and inclose a cavity that appears from its origin to be filled with a dense grunions masa. The eight cells expand into closely compressed radii,
arranged side by aide, increasing the circumference and depth of the whole body, whilst red granules are gradually deposited upon their inner wall. The dark contents are meanwhile developed into other cells, so that in the perfect organ a conical cell projects from the cell forming the pediele into the cavity, and a oylindricai cell is formed from the middle of each of the eight cells of the wall. These now cells, which likewise contain pale-red granules, bear on their free extremity several spherical or truncated cylindrical cells, from which project many long filaments composed of minute cells. The spherical cells and the filaments form a dense coil in the centre of the cavity. In each separate cell of tho filament wo at first see a grumous mass, which however subsequently disappears, giving place to a apiral fibre coiled up in two or three turns, and which manifests a peculiar motion on escaping from its cell. These mysterious organs have, as yet., without any reason, been termed anthem.' There is however an analogy between these organs and the so-called spermatozoids of other Cryptogamia, that would lead to the inference that they perform the same functions. (ItereonecrioN, VEGETATILF..] In addition to these organs, Montague has recently described hulbilli as present in the Charamr, by which, ho says, the species are frequently propagated.
The Characeesr are also highly interesting on account of the facility with which they exhibit the circulation of their fluids, and because of the light they thus appear to throw upon some of the more obscure of the phenomena of vegetable life. If one of the tubes of a Chars be observed under a pretty good microscope, by the aid of transmitted light, the fluid it contains will bo distinctly seen to have a motion up ono aide of each tube, down the other, and then up again, after tho manner of a jack-chain ; and this goes on continually as long as the plant remains alive. No spectacle that we are acquainted with is more beautiful than this, if it is well seen with the aid of a good microscope. This movement wee first described by Arnici. It has led to the examination of other water plants; in most of which the name kind of circulation can be detected. The best account of these move ments, with drawings, is that published by Varley in the 'Transactions of the Microscopical Society,' vol. ii. (Crews's.] ,Remains of (Maracas are frequently found in the fresh-water Tertiary deposits, but not lower down. The species are met with almost everywhere in stagnant water in Europe, Asia, Africa, North and South America, and Australia. They are most prevalent in temperate climes. The species of Chars are of no known use. The stems of the species which are calcareous often present beautiful examples of crystals of carbonate of lime. They are easily cultivated in glass vessels, which is often done for the sake of examining their circulation under the microscope. In the Chore this can only be done after removing the calcareous incrustation, but in Nitrite it is Peen without any preparation. The family has three genera and thirty-five species. Their relations are evidently with the A/gm on the one hand, and the Eau jai:Lame on the other.